Lock eoe bank-vaults



STATES PATENT oramai MARCUS R. `STEPHENSON AND OLIVER EDWARDS, OF BOSTON, MASSACHUSETTS.

Loox Foa BANK-VAULTS, sarnsac;

specification of Letters Patent No. 3,546, dated April 17, 1844.

To all 'whom it may concern.' Be it known thatI we, MARCUS R. SrnPI-InN--` soN and OLIVER EpwARDs, of Boston, in` the county of Suffolk and State of Massachusetts,

haveinvented a certain new and useful Im` provementin Locks to be Applied to Bank- Vaults, Doors of Safes, &c., and that the following specification of the same, taken in connection with the accompanying drawmain bolt has a suitable circular cavity formed in it, within which (cavity) a circular lever or plate N, (Fig.` 2), is placed and turns upon a suitable pin w inserted in the bolt. The position of the lever or plate N is shown by dotted lines in Fig.` l. The plate il has a slot O cut in one side of it, and an arm P projecting from it, at the lower side of the slot O, as seen in Fig. 2. The stud. R, which operates in the slots of the rising slide plates, is secured directly to the upper part of the plate N,as seen in Fig. 2, and theiupper. part of themain bolt is cut away (as seen atQ, Fig. 1,) in order to permit a lateral `movement of the stud.

Now, whenever the lock is attempted to be picked (by` the application of pressure to the main bolt, inthe usual manner), and the main bolt is forcedback, the rearsideor edge of the stud R `will be thrown against the rear sides'of the front verticalmslots ofthe series ofysliding plates, and` consequently will elevate the arm -P ofthe plate `N directly linffront of the fixed studM` of the lock case, thus preventingthe further recession of the bolt, and throwing all the strain, which would `otherwise come upon the sliding plates, immediately upon the fixed stud M. Then themain bolt is thrown forward by the key the arm P will be depressed again, below the stud M, or into a proper position to permit the full recessionV f of the bolt when thrown back by the key` the elongated slot L being formed of suffi retreat, or i passage back, of the bolt. i

cient length to permitthe full Having thus set fortli `our improvement we shall claim- The combination of appendages to the main bolt, the sliding plates, lock case and stud R; the said appendages being a bent lever or plate N (having an arm P extending from it in the manner before described)` and the fixed stud M of the lock casegAt-he usual stud R being made to extend from the plate N andthe plate N being made movable upona fulcrum a: applied to the main bolt and the whole being otherwise adapted to the sliding plates and other parts, and operating substantially in the manner gnl for the purpose as herein before speci- In testimonythat the above is a correct specificationwe have hereto set our signatures this eighth day of February, A.`

MARCUS R. STEPHENSON. oLivEn EDwARDs. i Witnesses: i

i R. H. EDnY, JOHN NOBLE. 

